Melon Lord

If the number of MTG cards in your
collection is higher than the number of
cards in each of your opponent's
collections, you become the melon lord.
(The melon lord has "at the beginning of your
upkeep, create a 0/10 green Melon creature
token." you remain the melon lord until
you die in real life, at which point your
firstborn child becomes the melon lord.)